A type of drilling equipment known as a blast hole drill is widely used in surface mining and quarrying operations to drill holes of moderate depth. Explosives are lowered to the bottom of these holes and detonated to break up rock and other hard earth formations. This permits the excavation of the material disintegrated by the blast and allows expansion of the area being mined or quarried. This equipment is typically mobile--being mounted on a vehicle that travels on crawlers. The vehicle has a cab for operating personnel and a housing for the machinery that drives the unit. A long, pivoting mast or drill tower is disposed horizontally when the unit is on the move, and is set upright for vertical drilling operations. The mast carries a number of individually stored pipes arranged longitudinally therein. These pipes are connected one at a time in a drill string as a hole is being drilled. A movable carriage on the mast moves down and up the mast as the pipe moves into and out of the ground. An air hose supplies air to the drill string and power lines supply power to the carriage. The air hose and supply lines run from the machine housing up to the carriage and must include slack in order to be able to move up and down with the carriage. This slack hangs down and can get entangled with or damaged by the mast. In order to limit damage to the air hose and the supply lines, a tray has been attached to the mast, and the slack laid in the tray. Often, however, the slack hose or lines would get entangled in the tray, or would fall out of the tray when the mast was moved from its vertical position, such as in certain mining operations, where it is advantageous to position the mast at an angle, up to 30.degree., to drill a hole at that angle.